RVSuppliesPlus@RVSuppliesPlus.com
This is a fastener used in the assembly of the pump. Fasteners in wetted or marine service are commonly stainless steel to resist corrosion.
This cap screw is stainless steel, hex head, 5/8-11 thread, 1.75 inch length. Always match by the MP Pumps part number 36606 listed on your equipment parts diagram, since dimensions and material vary across the MP Pumps lineup even for parts with the same common name.
Not sure this is the right part? Send us a picture of your Pump Plate to https://www.clrmarine.com/Contact-Us and the CLR Marine team will confirm the correct cap screw.